This application is based on Japanese Patent Application Nos. 2000-118564 filed Apr. 19, 2000 and 2000-123295 filed Apr. 24, 2000, the content of which is incorporated hereinto by reference.
1. Field of the Invention
The present invention relates to a joint device, an ink jet apparatus having the joint device, and an ink supplying device and method.
2. Description of the Related Art
Conventional ink jet recording apparatuses include, what is called, a serial scan type that comprises a recording head acting as recording means and an ink tank acting as an ink vessel, both being replaceably mounted on a carriage movable in a main scanning direction. This recording method comprises sequentially recording an image on a recorded medium by repeating a main scan of the carriage with the recording head and the ink tank mounted thereon and a subscan of the recorded medium.
With this recording method, an image can be recorded on a recorded medium of a large size such as A1 or A0 by increasing the movement width of the carriage. Since, however, the image is recorded on the large screen using a large amount of ink, this method requires an increase in the amount of ink accommodated in the ink tank, thereby increasing the weight of the entire carriage and proportionally an inertia force applied when the carriage is moved. To move the carriage at a high speed against the inertia force, a drive motor for the carriage must provide a high drive power, thus disadvantageously increasing the price of the entire recording apparatus. Further, the increase in the weight of the entire carriage also increases a force required to zero the acceleration of the carriage against the inertia force when the carriage reverses its direction at the turning point of a round-trip main scan; the reaction force to this force causes the entire recording apparatus to vibrate significantly. Thus, it is difficult to increase the movement speed of the carriage.
On the other hand, if the amount of ink accommodated in the ink tank is reduced to lighten the carriage, the ink tank must more frequently be replaced and the replacement must be carried out during a recording operation.
One of the solutions proposed for such an ink tank replacement problem is the technique described in Japanese Patent Application Laid-open No. 9-24698 (1997). With this conventional technique, a closed bias-bag-type ink vessel is connected to a recording head and an auxiliary ink vessel is connected to the bias-bag-type ink vessel so that the bias-bag-type ink vessel is refilled with an ink from the auxiliary ink vessel. The bias-bag-type comprises a bag for accommodating the ink and accommodates the ink therein under such negative pressure that hinders the leakage of the ink from an ink ejection port of the recording head. This negative pressure is used to refill the bias-bag-type ink vessel with the ink from the auxiliary ink vessel.
The bag of this bias-bag-type ink vessel collapses gradually to have its volume decrease with an increase in the amount of ink ejected from the recording head, that is, the amount of ink used. Once the volume of the bag decreases down to a predetermined value or smaller, a stopper to a supply port formed in the bias-bag-type ink vessel is opened and the supply port is connected to the auxiliary ink vessel. As a result, the negative pressure in the bag of the bias-bag-type ink vessel allows the ink to be supplied from the auxiliary ink vessel to the inside of the bag. When the amount of ink accommodated in the bag reaches a maxim value, the negative pressure in the bag becomes xe2x80x9czeroxe2x80x9d to automatically stop the ink refilling. Thus, according to this conventional technique, the negative pressure can be used to automatically stop the ink refilling without the needs for control using a pressure sensor, a volume detecting sensor, or the like.
The upper limit on the negative pressure in the bias-bag-type ink vessel is determined based on a tradeoff with the ink ejection force with which the recording head ejects the ink. This is because an excessively high negative pressure reduces the ink ejection force of the recording head, which thus cannot eject the ink. Accordingly, the negative pressure must be determined within the range of the best ink ejection conditions for the recording head. Further, the heat position of the ink in the auxiliary ink vessel must be set below that of the ink in the bias-bag-type ink vessel. With a too large difference in head position, the ink refilling is disabled even if the negative pressure in the bias-bag-type ink container is determined depending on the ink ejection conditions for the recording head.
Thus, this conventional technique includes a special device for setting the vertical height position of the auxiliary ink vessel relative to the bias-bag-type ink vessel. The inclusion of such a device, however, disadvantageously increases the size of the recording apparatus main body and costs thereof. Further, if, during ink refilling, air enters an ink channel from a portion thereof, the ink channel connecting the auxiliary ink vessel to the bias-bag-type ink vessel, the air moves to the inside of the bias-bag-type ink vessel to substantially reduce the amount of ink accommodated in the bias-bag-type ink vessel. Furthermore, if a large amount of air enters the ink channel, the inside of the bag of the bias-bag-type ink vessel is filled with air to prevent further ink refilling. Moreover, the bias-bag-type ink vessel comprises a telescopic bag member forming the bag and movable parts such as spring members for inflating the bag member, so that the size reduction of the ink vessel is limited, thus increasing the complexity, weight, and manufacturing costs of this structure.
On the other hand, in a joint portion for connecting an ink intake port formed in the ink vessel to the auxiliary ink vessel, a force required to close the joint must be increased so as to preclude the ink from leaking from the auxiliary ink tank. As a result, high power is required to open and close a joint supply port.
The present invention is adapted to solve the problems of the prior art, and an object thereof is to provide a joint device for refilling an ink tank with an ink which has a simple configuration but which can be reliably implemented using low power, thus reducing the weight and costs of a recording apparatus and making it more reliable, as well as an ink jet recording apparatus using the joint device, and an ink supplying device and method.
To attain the above object, the present invention provides a joint device for connecting and separating an ink tank capable of taking in an ink through an ink intake port to and from ink supply means connected to the ink intake port to take the ink from a refilling tank in the ink tank, the joint device being characterized by comprising a supply pipe having an ink supply port disposed therein, closing means composed of an elastic member, for opening and closing the ink supply port, deformation means for deforming the closing means, and urging means for urging the deformation means. Accordingly, the joint device for refilling the ink tank with an ink can be produced to have the simple configuration and can be reliably implemented by using low power despite the simple configuration, thereby reducing the weight of a recording apparatus and making the recording apparatus more reliable.
The joint device of the present invention is also characterized in that the deformation means operates during a connection operation in such a manner as to relieve the deformation of the closing means and then slide over the supply pipe. The deformation means thus scrapes and removes attachments such as dirt and ink which adhere to an abutment surface, to prevent leakage from the joint due to the attachments.
The joint device of the present invention is further characterized in that the closing means has a sucker-shaped portion additionally formed therein and which is sufficiently deformed to allow the deformation means to operate, thereby ensuring that the ink supply port is closed to prevent the leakage and drying of the ink.
The joint device of the present invention is further characterized in that recesses and projections are formed near the ink intake port so that the sucker-shaped portion is deformed in such a manner as to rub against the recesses and projections. Consequently, attachments such as dirt and ink which adhere to the abutment surface can be scraped for cleaning, thereby precluding leakage from the joint due to the attachments to reliably prevent the leakage of the ink.
The present invention provides an ink jet recording apparatus having an a joint device for connecting and separating an ink tank capable of taking in an ink through an ink intake port to and from ink supply means connected to the ink intake port to take the ink from a refilling tank in the ink tank, the ink jet recording apparatus being characterized by comprising a supply pipe having an ink supply port disposed therein, closing means composed of an elastic member, for opening and closing the ink supply port, deformation means for deforming the closing means, and urging means for urging the deformation means. Accordingly, the joint device for refilling the ink tank with an ink can be produced to have the simple configuration and can be reliably implemented using low power despite the simple configuration, thereby reducing the weight of the recording apparatus and making the recording apparatus more reliable.
The ink jet recording apparatus of the present invention is also characterized in that the deformation means operates during a connection operation in such a manner as to relieve the deformation of the closing means and then slide over the supply pipe. The deformation means thus scrapes and removes attachments such as dirt and ink which adhere to an abutment surface, to prevent leakage from the joint due to the attachments.
The ink jet recording apparatus of the present invention is further characterized in that the closing means has a sucker-shaped portion additionally formed therein and which is sufficiently deformed to allow the deformation means to operate, thereby ensuring that the ink supply port is closed to prevent the leakage and drying of the ink.
The ink jet recording apparatus of the present invention is further characterized in that recesses and projections are formed near the ink intake port so that the sucker-shaped portion is deformed in such a manner as to rub against the recesses and projections. Consequently, attachments such as dirt and ink which adhere to the abutment surface can be scraped for cleaning, thereby precluding leakage from the joint due to the attachments to reliably prevent the leakage of the ink.
The present invention provides an ink jet recording apparatus comprising an ink tank capable of taking in an ink through an ink intake port and ink supply means capable of taking an ink from a refilling tank in the ink tank by means of negative pressure introduced into the ink tank through a suction port therein, the ink jet recording apparatus being characterized in that the suction port has gas-liquid separating means for transmitting gases therethrough while not transmitting the ink therethrough. Thus, air as a gas is separated from the ink, so that only the air can be discharged from the ink tank, while the ink can be supplied.
The ink jet recording apparatus of the present invention is characterized in that the gas-liquid separating means is selected from polytetrafluoroethylene and similar porous resin materials which transmit gases therethrough while not transmitting liquids therethrough. Accordingly, the gas-liquid separating means can be properly produced using an inexpensive material.
The present invention provides an ink jet recording apparatus that can record an image on a recorded medium using an ink jet recording head capable of ejecting an ink supplied from an ink tank, the ink jet recording apparatus being characterized by comprising negative-pressure introducing means capable of introducing negative pressure into the ink tank, ink supplying means for capable of supplying the ink to an interior of the ink tank using the negative pressure in the ink tank, gas-liquid separating means provided in a negative-pressure introducing path located between the ink tank and the negative-pressure introducing means, for transmitting gases therethrough while not transmitting the ink therethrough, and isolation means capable of separating a middle site of the negative-pressure introducing path located between the gas-liquid separating means and the negative-pressure introducing means. Accordingly, the ink tank can be reliably refilled with the ink using the simple configuration, thereby reducing the weight and costs of the recording apparatus and making the recording apparatus more reliable.
The ink jet recording apparatus of the present invention is also characterized in that the gas-liquid separating means is supported by the ink tank and is movable between at least two positions including a first position used while the ink is not supplied and a second position used during an ink supply. Consequently, the gas-liquid separating means is prevented from contacting with the ink at the first position and thus from having its performance degraded.
The ink jet recording apparatus of the present invention is further characterized in that the isolation means has a connection portion to which the middle site of the negative-pressure introducing path is separably connected, thereby ensuring that the negative-pressure introducing path is connected to and separated from the ink tank for proper connection and isolation.
The ink jet recording apparatus of the present invention is further characterized by having movement means for moving the ink tank so that when the ink tank moves to a predetermined ink supplying position and a predetermined home position, the isolation means connects the middle site of the negative-pressure introducing path to the ink tank and so that when the ink tank moves away from the ink supplying position and the home position, the isolation means isolates the middle site of the negative-pressure introducing path from the ink tank. Accordingly, the middle site of the negative-pressure introducing path can be reliably separated from the ink tank.
The ink jet recording apparatus of the present invention is characterized by having the movement means for moving the ink tank so that when the ink tank moves to a predetermined ink supplying position, the isolation means connects the middle site of the negative-pressure introducing path to the ink tank and so that when the ink tank moves away from the ink supplying position, the isolation means isolates the middle site of the negative-pressure introducing path from the ink tank. Consequently, the ink tank can be properly moved and reliably isolated.
The ink jet recording apparatus of the present invention is characterized in that when the ink tank moves away from the ink tank supply position, the gas-liquid separating means is driven to the first position and in that when the ink tank moves to the ink tank supply position, the gas-liquid separating means is driven to the second position. Accordingly, the gas-liquid separating means can be properly connected and separated in connection with the movement of the ink tank.
The ink jet recording apparatus of the present invention is further characterized in that while the gas-liquid separating means is being driven between the first and second positions, a part of the negative-pressure introducing path is in communication with the atmosphere. Thus, during the movement, the negative-pressure introducing path is prevented from undergoing the negative pressure.
The ink jet recording apparatus of the present invention is further characterized in that the movement means moves the ink jet recording head together with the ink tank. Consequently, the movement means may be of a minimum size; the use of excess-sized movement means is avoided.
The ink jet recording apparatus of the present invention is further characterized in that the gas-liquid separating means is a gas-transmitting film composed of polytetrafluoroethylene or a similar porous resin material. Accordingly, the gas-liquid separating means can be inexpensively produced to have a simple configuration.
The ink jet recording apparatus of the present invention is also characterized in that the gas-liquid separating means is a gas-transmitting film composed of porcelain, unglazed pottery, ceramic, or a similar porous material. Thus, the gas-liquid separating means can be inexpensively produced to have a simple configuration.
The ink jet recording apparatus of the present invention is further characterized in that the gas-liquid separating means undergoes an oil-repelling process. As a result, the simple means can be used to improve the oil-repelling effect of the gas-liquid separating means.
The ink jet recording apparatus of the present invention is further characterized in that the ink jet recording head has an elcetrothermal converter for generating thermal energy as energy required to eject the ink. Consequently, the ink can be appropriately ejected for proper recording.
The present invention provides an ink supplying device characterized by comprising negative-pressure introducing means capable of introducing negative pressure into the ink tank, ink supplying means for capable of supplying the ink to an interior of the ink tank using the negative pressure in the ink tank, gas-liquid separating means provided in a negative-pressure introducing path located between the ink tank and the negative-pressure introducing means, for transmitting gases therethrough while not transmitting the ink therethrough, and isolation means capable of separating a middle site of the negative-pressure introducing path located between the gas-liquid separating means and the negative-pressure introducing means. Accordingly, the ink tank can be reliably refilled with the ink using the simple configuration, thereby reducing the weight and costs of the recording apparatus and making the recording apparatus more reliable.
The ink supplying device of the present invention is also characterized in that the gas-liquid separating means is supported by the ink tank and is movable between at least two positions including a first position used while the ink is not supplied and a second position used during an ink supply. Thus, the gas-liquid separating means can be properly connected and separated in connection with the movement of the ink tank.
The ink supplying device of the present invention is further characterized in that the isolation means has a connection portion to which the middle site of the negative-pressure introducing path is separably connected, thereby ensuring that the negative-pressure introducing path is connected to and separated from the ink tank for proper connection and isolation.
The ink supplying device of the present invention is further characterized by having movement means for moving the ink tank so that when the ink tank moves to a predetermined ink supplying position and a predetermined home position, the isolation means connects the middle site of the negative-pressure introducing path to the ink tank and so that when the ink tank moves away from the ink supplying position and the home position, the isolation means isolates the middle site of the negative-pressure introducing path from the ink tank. Consequently, the ink tank can be reliably refilled with the ink using the simple configuration, thereby reducing the weight and costs of the recording apparatus and making the recording apparatus more reliable.
The ink supplying device of the present invention is characterized by having movement means for moving the ink tank so that when the ink tank moves to a predetermined ink supplying position, the isolation means connects the middle site of the negative-pressure introducing path to the ink tank and so that when the ink tank moves away from the ink supplying position, the isolation means isolates the middle site of the negative-pressure introducing path from the ink tank. Consequently, the ink tank can be properly moved and reliably isolated.
The ink supplying device of the present invention is characterized in that when the ink tank moves away from the ink tank supply position, the gas-liquid separating means is driven to the first position and in that when the ink tank moves to the ink tank supply position, the gas-liquid separating means is driven to the second position. Accordingly, the gas-liquid separating means can be properly connected and separated in connection with the movement of the ink tank.
The ink supplying device of the present invention is further characterized in that while the gas-liquid separating means is being driven between the first and second positions, a part of the negative-pressure introducing path is in communication with the atmosphere. Thus, during the movement, the negative-pressure introducing path is prevented from undergoing the negative pressure.
The ink supplying device of the present invention is further characterized in that the gas-liquid separating means is a gas-transmitting film composed of polytetrafluoroethylene or a similar porous resin material. Accordingly, the gas-liquid separating means can be inexpensively produced to have a simple configuration.
The ink supplying device of the present invention is also characterized in that the gas-liquid separating means is a gas-transmitting film composed of porcelain, unglazed pottery, ceramic, or a similar porous material. Consequently, the gas-liquid separating means can be inexpensively produced to have a simple configuration.
The ink supplying device of the present invention is further characterized in that the gas-liquid separating means undergoes an oil-repelling process. Thus, the simple means can be used to improve the oil-repelling effect of the gas-liquid separating means.
The present invention provides an ink supplying method characterized in that the method includes negative-pressure introducing means, gas-liquid separating means provided in a negative-pressure introducing path capable of introducing a negative pressure into an ink tank, the gas-liquid separating means transmitting gases therethrough while not transmitting inks therethrough, and isolation means provided in a middle site of the negative-pressure introducing path located between the gas-liquid separating means and the negative-pressure introducing means, the isolation means being capable of isolating the middle site, in that when the ink tank moves to a predetermined ink supplying position and a predetermined home position, the middle site of the negative-pressure introducing path is connected, in that when the ink tank moves to the ink supplying position, the gas-liquid separating means is located at the second position and the negative pressure is introduced into the ink tank through the negative-pressure introducing path, so that the ink is supplied to an interior of the ink tank using the negative pressure in the ink tank, in that when or after the ink comes into contact with the gas-liquid separating means, the gas-liquid separating means stops introducing the negative pressure into the ink tank, in that when the ink tank leaves the ink supplying position and the home position, the middle site of the negative-pressure introducing path is isolated, and in that when the ink tank leaves the ink supplying position, the gas-liquid separating means is located at the first position. Accordingly, the ink tank can be reliably refilled with the ink using the simple configuration, thereby reducing the weight and costs of the recording apparatus and making the recording apparatus more reliable.
The present invention provides an ink supplying method characterized in that the method includes gas-liquid separating means provided in a negative-pressure introducing path capable of introducing a negative pressure into an ink tank, the gas-liquid separating means transmitting gases therethrough while not transmitting inks therethrough, and isolation means provided in a middle site of the negative-pressure introducing path located between the gas-liquid separating means and the negative-pressure introducing means, the isolation means being capable of isolating the middle site, in that when the ink tank moves to a predetermined ink supplying position, the middle site of the negative-pressure introducing path is connected, the gas-liquid separating means is located at the second position, and the negative pressure is introduced into the ink tank through the negative-pressure introducing path, so that the ink is supplied to an interior of the ink tank using the negative pressure in the ink tank, in that when or after the ink comes into contact with the gas-liquid separating means, the gas-liquid separating means stops introducing the negative pressure into the ink tank, in that when the ink tank leaves the ink supplying position, the middle site of the negative-pressure introducing path is isolated and the gas-liquid separating means is located at the first position. Accordingly, the ink tank can be reliably refilled with the ink using the simple configuration, thereby reducing the weight and costs of the recording apparatus and making the recording apparatus more reliable.
The above and other objects, features and advantages of the present invention will become more apparent from the following description of embodiments thereof taken in conjunction with the accompanying drawings.